package sandbox

import (
	"testing"

	"go.starlark.net/starlark"
)

func runRoutingScript(t *testing.T, script string) starlark.StringDict {
	t.Helper()
	mod := BuildRoutingModule()
	predeclared := starlark.StringDict{"routing": mod}
	globals, err := starlark.ExecFile(&starlark.Thread{Name: "test"}, "test.star", script, predeclared)
	if err != nil {
		t.Fatal(err)
	}
	return globals
}

func runRoutingScriptErr(t *testing.T, script string) error {
	t.Helper()
	mod := BuildRoutingModule()
	predeclared := starlark.StringDict{"routing": mod}
	_, err := starlark.ExecFile(&starlark.Thread{Name: "test"}, "test.star", script, predeclared)
	return err
}

func TestRoutingEvaluate_SingleMatch(t *testing.T) {
	globals := runRoutingScript(t, `
result = routing.evaluate([
    {"field": "priority", "op": "eq", "value": "high", "target": "escalation"},
], {"priority": "high"})
`)
	result := globals["result"]
	if s, ok := result.(starlark.String); !ok || string(s) != "escalation" {
		t.Fatalf("expected 'escalation', got %v", result)
	}
}

func TestRoutingEvaluate_FirstMatchWins(t *testing.T) {
	globals := runRoutingScript(t, `
result = routing.evaluate([
    {"field": "amount", "op": "gt", "value": 100, "target": "big"},
    {"field": "amount", "op": "gt", "value": 50,  "target": "medium"},
], {"amount": 200})
`)
	result := globals["result"]
	if s, ok := result.(starlark.String); !ok || string(s) != "big" {
		t.Fatalf("expected 'big', got %v", result)
	}
}

func TestRoutingEvaluate_NoMatch(t *testing.T) {
	globals := runRoutingScript(t, `
result = routing.evaluate([
    {"field": "status", "op": "eq", "value": "done", "target": "finish"},
], {"status": "pending"})
`)
	if globals["result"] != starlark.None {
		t.Fatalf("expected None, got %v", globals["result"])
	}
}

func TestRoutingEvaluate_EmptyRules(t *testing.T) {
	globals := runRoutingScript(t, `
result = routing.evaluate([], {"x": 1})
`)
	if globals["result"] != starlark.None {
		t.Fatalf("expected None, got %v", globals["result"])
	}
}

func TestRoutingEvaluate_AllOperators(t *testing.T) {
	globals := runRoutingScript(t, `
# exists
r1 = routing.evaluate([{"field": "x", "op": "exists", "value": "", "target": "yes"}], {"x": 1})
# not_exists
r2 = routing.evaluate([{"field": "x", "op": "not_exists", "value": "", "target": "yes"}], {"y": 1})
# eq
r3 = routing.evaluate([{"field": "s", "op": "eq", "value": "abc", "target": "yes"}], {"s": "abc"})
# neq
r4 = routing.evaluate([{"field": "s", "op": "neq", "value": "abc", "target": "yes"}], {"s": "xyz"})
# gt
r5 = routing.evaluate([{"field": "n", "op": "gt", "value": 10, "target": "yes"}], {"n": 20})
# lt
r6 = routing.evaluate([{"field": "n", "op": "lt", "value": 10, "target": "yes"}], {"n": 5})
# gte
r7 = routing.evaluate([{"field": "n", "op": "gte", "value": 10, "target": "yes"}], {"n": 10})
# lte
r8 = routing.evaluate([{"field": "n", "op": "lte", "value": 10, "target": "yes"}], {"n": 10})
# in
r9 = routing.evaluate([{"field": "s", "op": "in", "value": ["a", "b", "c"], "target": "yes"}], {"s": "b"})
# contains
r10 = routing.evaluate([{"field": "s", "op": "contains", "value": "ell", "target": "yes"}], {"s": "hello"})
`)
	for _, name := range []string{"r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10"} {
		v := globals[name]
		if s, ok := v.(starlark.String); !ok || string(s) != "yes" {
			t.Errorf("%s: expected 'yes', got %v", name, v)
		}
	}
}

func TestRoutingEvaluate_TypeCoercion(t *testing.T) {
	globals := runRoutingScript(t, `
# Numeric string vs int
r1 = routing.evaluate([
    {"field": "n", "op": "gt", "value": 10, "target": "yes"},
], {"n": "20"})

# Int equality via string normalization
r2 = routing.evaluate([
    {"field": "n", "op": "eq", "value": 42, "target": "yes"},
], {"n": 42})
`)
	for _, name := range []string{"r1", "r2"} {
		v := globals[name]
		if s, ok := v.(starlark.String); !ok || string(s) != "yes" {
			t.Errorf("%s: expected 'yes', got %v", name, v)
		}
	}
}

func TestRoutingEvaluate_BadInput(t *testing.T) {
	// rules must be a list
	err1 := runRoutingScriptErr(t, `routing.evaluate("bad", {})`)
	if err1 == nil {
		t.Fatal("expected error for non-list rules")
	}

	// data must be a dict
	err2 := runRoutingScriptErr(t, `routing.evaluate([], "bad")`)
	if err2 == nil {
		t.Fatal("expected error for non-dict data")
	}

	// rule missing required fields
	err3 := runRoutingScriptErr(t, `routing.evaluate([{"field": "x"}], {})`)
	if err3 == nil {
		t.Fatal("expected error for incomplete rule")
	}
}

func TestRoutingEvaluate_MissingFields(t *testing.T) {
	globals := runRoutingScript(t, `
# Field not in data — eq should not match
r1 = routing.evaluate([
    {"field": "absent", "op": "eq", "value": "x", "target": "bad"},
], {"other": "y"})

# not_exists matches when field is absent
r2 = routing.evaluate([
    {"field": "absent", "op": "not_exists", "value": "", "target": "good"},
], {"other": "y"})
`)
	if globals["r1"] != starlark.None {
		t.Fatalf("r1: expected None for missing field, got %v", globals["r1"])
	}
	if s, ok := globals["r2"].(starlark.String); !ok || string(s) != "good" {
		t.Fatalf("r2: expected 'good', got %v", globals["r2"])
	}
}